1,1-dibromo-1-cyanomethanesulfonamides

ABSTRACT

THE COMPOUNDS OF THE FORMULA   NC-C(-BR)2-SO2-N(-R1)-R2   WHEREIN R1 AND R2 INDEPENDENTLY REPRESENT HYDROGEN OR A LOWER ALKYL GROUP. THE COMPOUNDS ARE PREPARED BY REACTING A 1-CYANOMETHANESULFONAMIDE WITH BROMINE IN AQUEOUS ALKALINE MEDIUM. THE COMPOUNDS HAVE ANTIMICROBIAL ACTIVITY.

United States Patent O 3,836,566 1,1-DIBROMO-l-CYANOMETHANESULFON-AMIDES Christian T. Goralski, Midland, Mich., assignor to The DowChemical Company, Midland, lVIich. No Drawing. Filed May 25, 1973, Ser.No. 364,174 Int. Cl. C07c 121/00, 121/16' US. Cl. 260-465.5 R ClaimsABSTRACT OF THE DISCLOSURE The compounds of the formula wherein R and Rindependently represent hydrogen or a lower alkyl group. The compoundsare prepared by reacting a l-cyanomethanesulfonamide with bromine inaqueous alkaline medium. The compounds have antimicrobial activity.

BACKGROUND 'OF THE INVENTION The starting materials for several of thecompounds of this invention, l-cyanome-thanesulfonamide andN-isobutyl-l-cyanomethanesulfonamide are known; US. Pat. 2,978,482 andJ. Chem. Soc., 1971, C, 2151. They have no useful antimicrobialactivity. No homologs, isomers or closely related analogs of thecompounds of this invention are known.

SUMMARY OF THE INVENTION This invention concerns1,l-dibromo-l-cyanomethanesulfonamides corresponding to the formulawherein R and R independently represent hydrogen or a lower alkyl group.The componnds are fine, white, crystalline solids which are soluble inwater, and chlorinated solvents such as methylene chloride orchloroform, depending on the nature of the R and R groups. The compoundshave antimicrobial activity and are particularly useful as slimicidesfor cooling towers, paper mills and the like. As used herein, loweralkyl designates an alkyl group having from 1, to 2, to 3, to 4 carbonatoms.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The compounds are prepared inthe following way. The starting materials, 1-cyanomethanesulfonamide orN- 'alkyl analogs are suspended in water containing 2 moles of bromineper mole of starting material or substantially about to 50% excess overthe stoichiometric requirements of 2 moles of bromine per mole ofstarting material. A larger excess may be used but is not necessary.However, best results are achieved when substantially two moles ofbromine per mole of starting material are utilized. Aqueous metalhydroxide is added to the resulting suspension while it is mixed andcooled in an ice bath, in amount suflicient to neutralize evolvedhydrogen bromide of reaction. The reaction mixture is then stirred3,836,566 Patented Sept. 17, 1974 lower alkanols such as methanol orethanol, to give the title compound as a white, crystalline solid. Thestructure is established by infrared and mass spectroscopy.

The following examples additionally describe representative specificembodiments and the best mode contemplated by the inventor of carryingout the invention.

EXAMPLE 1,1-dibromo-l-cyanomethanesulfonamide -'In a 250 ml. flaskequipped with a magnetic stirrer and a dropping funnel, place 2.40 g.(0.02 mol) of l-cyanomethanesulfonamide, 30 ml. of water, and 6.40 g.(0.04 mol) of bromine The resulting solution is cooled in 'an ice-bath,and a solution of 1.60 g. (0.04 mol) of sodium hydroxide in 30 ml. ofwater is added dropwise thereto with stirring. After the addition iscompleted, the reaction mixture is stirred for one hour, then extractedwith chloroform. The chloroform exract is dried and the chloroform isremoved in vacuo to give a white solid. The solid is recrystallized fromether/hexane to give the title compound as a white, crystalline solid,mp. 163-164 C.

In a similar manner, analogous compounds wherein one or both of theamido nitrogens is substituted with a lower alkyl group are prepared.There are thereby obtained, for example,1,l-dibromo-1-cyano-N,N-dimethylmethanesulfonam-ide,1,l-dibromo-l-cyano-N,N diethylmethanesulfonamide, and 1,1-dibromo-N-isobutyl lcyanometlranesulfonamide.

The compounds of the invention are employed as Iantimicrobials for thecontrol of bacteria, fungi and yeasts. This is not to suggest that allof the compounds are equally effective against all of the organisms atthe same concentrations. For such uses, the compounds can be employed inan unmodified form or dispersed on a ttinely divided solid and employedas dusts. Such mixtures can also be dispersed in water with the aid of asurface active agent and the resulting emulsions employed as sprays. Inother procedures, the products can be employed as active constituents insolvent solutions, oil-in-water or water-in-oil emulsions. The augmentedcompositions are adapted to be formulated as concentrates andsubsequently diluted with additional liquid or solid adjuvants toproduce the ultimate treating compositions. Good results are obtainedwhen employing compositions containing antimicrobial concentrations andusually from about 50 to 10,000 parts by weight of one or more of thecompounds per million parts of such compositions.

In representative operations, the compounds of the present inventionwhen tested for their activity as antimicrobials using conventional agardilution tests give complete or substantially complete growth inhibitionagainst P. aeruginosa and Sp Strain 10, E. coil, C. albicans, T.mentagro'phytes, B. subtilis, A. aerogenes, A. terreus, C. pelliculosa,S. typhosa, M. phlei, R. nigricans, C ips and C. fragans at 50 to 500ppm. of compound.

The starting materials for the compounds of this invention are preparedas follows: l-cyanomethanesulfonamide according to the procedure of J.'Weinstock, US. Pat. 2,978,482, and theN-alkyl-l-cyanomethanesulfonamides according to the procedure of M. P.Sammes er. al., J. Chem. Soc., 2151-(1971, C.). o

'Nc-oBm-som ,Tvherein R and R independently refiresent hydrogen or a 1to 4 carbon atom lower alkyl group.

2 Thecompound ofvClaim-l which is 1,1-dibromo-1-cyanomethancsulfonamide.

4. The compound of Claim 1 which is 1,1-dibromo-1-.cyanomethane-N,N-cliethylsulfonamide.

s. Thecom ouna bf 0 sum 1 which is LI-dibfoxho-N- iiQfi PYkl: zxn mqthnuvnmidq .H.

References Cited UNITED STATES PATENTS 2,978,482 11 1973 WeiiTstiok 26 04655 R T Q HER' REFERENCES: v Sainms et a1. 3. Chem. Soc., 1971 0. p.2151- 2155, I 7 Q JOSEPH P. B-RUST, Primary Examiner U.S.. C21. X12. 1

